Long-Term Trend of Gaseous Ammonia Over the United States: Modeling and Comparison With Observations.

ABSTRACT: The concentrations of atmospheric ammonia ([NH₃]) have been observed to be increasing over the United States in the last decade, especially in Eastern United States. It is important to understand this temporal trend and variation due to the role of NH₃ in particle formation and its ecological effects. Here the long-term trend of [NH₃] over the United States is investigated using GEOS-Chem, a global 3-D tropospheric chemistry model, and is corroborated with empirical evidence from the Ammonia Monitoring Network. Model simulations, consistent with observations, show increase in [NH₃] over the United States from 2001 to 2016, with magnitude largest in the East (~5% to 12%/year) and smallest in the West (~0% to 5%/year). Reasons for this are examined

SUBMITTER: Yu F 

PROVIDER: S-EPMC6473605 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature